a. Field of the Invention
The present invention relates to ophthalmic therapy, and in particular, methods and devices utilized in the ophthalmic theraputic procedure known as retinopexy, used in repairing partially detached and/or torn retinas.
b. Problems in the Art
Retinopexy involves injecting an air bubble to a specific location in a patient's eye to push a partially detached retina, caused by a retinal tear or break, into its appropriate position so that it can be treated for repair. It is most times used for tears or breaks in the retina located in the superior or upper portion of the eye, and which exist at or near the retina's periphery. It is advantageous in that, if successful, it eliminates the requirement of more intrusive surgery, such as intraocular surgery. This is an extremely delicate and critical procedure, as are most ophthalmic surgical procedures.
Presently, retinopexy is accomplished by utilizing a conventional handheld syringe. The ophthalmic surgeon must manually fill the conventional syringe with air or gas, manually insert the syringe needle into the patient's eye, visually monitor the location of the needle tip in the eye, and then delicately and steadily inject an accurate volume of air or gas to form a single air bubble to prop up the retina of the patient. Retinopexy injects a bubble into the eye, which migrates upwardly once expelled from the needle tip. The needle tip must be positioned very close to the damaged part of the retina and in an orientation which allows the bubble to expand and move against the tear to push it back into place.
Methods, such as are well known to those skilled in the art, are then used to cause the tear to stay in place, even after the bubble has moved or dissipated. This entire procedure thus avoids intraocular surgery and its effects and risks.
It is, of course, critically important to not only hold the needle vertically and maintain the accurate depth of the needle tip, but also to inject the gas so that one controlled-in-size bubble is formed. As can be well appreciated, this step requires a high level of skill to accomplish.
Not only does the surgeon have to accomplish all these tasks manually, usually with both hands, but also the minute parameters involved in treating the eye, along with the risk of significant damage to the eye by any unintended or unnecessary invasion of the eye, multiplies the difficulty and riskiness of such procedures.
It can therefore be seen that retinopexy with a conventional syringe requires the skill to keep the syringe as vertical as possible, insert the needle tip so as not to damage any other structure of the eye, such as the lens, position the needle tip appropriately to the required depth and location, and then operate the syringe satisfactorily to produce the necessary type of bubble, and the necessary location. Moreover, the surgeon must most times utilize some sort of a light source and magnification lens or scope to provide an adequate view of the needle tip in the eye.
The problems involved in present retinopexy methods reveal the need for improvements in this procedure. Operating a conventional syringe under such conditions requires reliance on a steady, correctly positioned, finely controlled injection by the surgeon's hands. Conventional needles are prone to injecting bubble trains, instead of one bubble. This could be the result of faulty expulsion of the gas from the syringe. Small bubbles and bubble trains usually cannot support the retina in the manner needed or they may obscure the surgeon's vision of the retinal damage. Furthermore, they may even pass through the retinal break, if small enough, and therefore provide opposing pressure to defeat the retinopexy procedure.
If the surgeon concentrates too much on steady injection of the gas to form a correct bubble, small movements in the needle tip may result in misplacement of the bubble.
The critical nature of the retinopexy procedure currently depends entirely on manual control of the conventional syringe. This simply is just not as reliable as might be desired in the art.
It is therefore a principal object of the present invention to improve over or solve the deficiencies and problems in the art.
Another object of the present invention is to provide a pneumatic retinopexy injector which eliminates a significant amount of reliance on manual control by the surgeon.
A further object of the present invention is to provide an injector as above described which is highly controllable.
Another object of the present invention is to provide an injector as above described which provides improved results for retinopexy.
A further object of the present invention is to provide an injector as above described which produces a reliable gas bubble for retinopexy.
Another object of the present invention is to provide an injector as above described which provides a controlled volume injection rate for retinopexy procedures.
Another object of the present invention is to provide an injector as above described which provides a controlled displacement rate for retinopexy procedures.
A further object of the present invention is to provide an injector as above described which is economical, efficient, reliable, and durable.
Another object of the present invention is to provide an injector as above described which is easily usable for repeated retinopexy procedures.
Another object of the present invention is to provide an injector as above described which facilitates easy filling.
These and other objects features and advantages of the present invention will become more apparent with reference to the accompanying specification and claims.